I have a Graphic 23, 6X9 roll film holder for my RB Graflex Series B. I would really prefer to have a 6X7. The Graphic 22 is 6X6. Hmmm, guess I need a Graphic 22.3

So I started shopping eBay for an RH-10 thinking it looks pretty similar. However, I quickly noticed that the mounting faces of the 22/23 and the RH's are different.

My 23 has a flat surface with a narrow groove cut across it that accommodates a standup metal lip at the top of the Series B's Graflok back. All the RH's I've seen have two raised ribs running across the top of the mounting face, and no groove. They're obviously not going to seat properly in the Series B.

Is there a version of the RH-10 holder that has the groove and no ribs and will fit the Series B? If so, what do I need to ask for / look for... and where do I look. Or do all RH-10's have the ribs and I need to do some machining?

the so-called ideal format,67 ,ideal because it enlarges to 810 w/o cropping, was only made for the graphic and graflok backs. it is lever wind, 10 exp for 120 or there is one for 20 exp on 220. you need one of these two plus a 12 exposure roll back for the graflex. you then have have the 12 opened up to 67 and you can then put in the insert from one of the graphic backs. you dont
need the whole graphic back if you can find an
insert. also dont get a real late 67 complete back or insert as it may not fit the
graflex back . these newer ones
are generally marked singer rather than graflex.